A light emitting diode (LED) is widely used as an illumination light source. The LED has the characteristic of a fast response speed, as compared to, for example, an incandescent lamp or a fluorescent lamp. With this characteristic, a visible light communication technology has been studied which performs a communication by making the LED flicker at a speed that cannot be recognized by the human eyes and superimposing information on the light emitted from the LED. Especially, the technique of superimposing information to be transmitted on the illumination light is also called an illumination light communication.
It has been considered that the visible light communication is used for a communication in a place where the use of radio waves is restricted, an information distribution limited to the range which light reaches such as indoors, or the intelligent transport system (ITS).
In the visible light communication, a technique has been suggested in which an apparatus receiving information superimposed on light from an illumination light source receives light reflected by an object from the illumination light source, and demodulates the information superimposed on the light.
Related technologies are disclosed in, for example, Japanese Laid-Open Patent Publication No. 2012-055582.